US9908730B2ActiveUtilityPatentIndex 72
Method for further processing thin glass and thin glass produced by such method
Est. expirySep 30, 2033(~7.2 yrs left)· nominal 20-yr term from priority
B32B 7/06B32B 17/065B65H 2515/31B65H 20/00C03C 3/076B65H 2701/18422B65H 2701/1712B65H 2701/17B65H 18/08B65H 23/00C03C 3/093C03C 3/087B65H 2801/61C03C 3/091B65H 23/105C03C 3/118B32B 17/06B32B 17/064B65H 18/28B32B 17/10
72
PatentIndex Score
6
Cited by
18
References
19
Claims
Abstract
A method for processing a thin glass is provided. The thin glass is subjected to a tensile stress σ app smaller than 1.15 · Min ( σ _ a - Δ a 0.4 · ( 1 - ln ( A ref A App Φ ) ) , σ _ e - Δ e 0.4 · ( 1 - ln ( L ref L App Φ ) ) ) , wherein σ a is a mean value of tensile stress at break for fractures in a surface of samples of the thin glass under bending stress, wherein σ a is a mean value of tensile stress at break for fractures emanating from an edge of the samples, wherein L ref is an edge length and A ref is a surface area of the samples, wherein Δ e and Δ a denote standard deviations of the mean values σ e and σ a , respectively, and wherein A app is a surface area of the thin glass, L app is a summated edge length of opposite edges of the thin glass, and Φ is a predefined maximum fracture rate within a period of time of at least half a year.
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1. A method for further processing a thin glass, comprising:
subjecting the thin glass to a tensile stress σ app smaller than
1.15
·
Min
(
σ
_
a
-
Δ
a
0.4
·
(
1
-
ln
(
A
ref
A
App
Φ
)
)
,
σ
_
e
-
Δ
e
0.4
·
(
1
-
ln
(
L
ref
L
App
Φ
)
)
)
,
wherein σ a is a mean value of a tensile stress at break for fractures in a surface of samples of the thin glass under bending stress,
wherein σ e is a mean value of a tensile stress at break for fractures emanating from an edge of the samples,
wherein L ref is an edge length of the samples and A ref is a surface area of the samples,
wherein Δ e and Δ a denote standard deviations of the mean values σ e and σ a , respectively, and
wherein A app is a surface area of the thin glass, L app is a summated edge length of opposite edges of the thin glass, and Φ is a predefined maximum fracture rate within a period of time of at least half a year.
2. The method as claimed in claim 1 , wherein the predefined maximum fracture rate Φ is 0.1 or less.
3. The method as claimed in claim 1 , wherein with the tensile stress σ app smaller than
0.93
·
Min
(
σ
_
a
-
Δ
a
0.4
·
(
1
-
ln
(
A
ref
A
app
Φ
)
)
,
σ
_
e
-
Δ
e
0.4
·
(
1
-
ln
(
L
ref
L
app
Φ
)
)
)
.
4. The method as claimed in claim 1 , further comprising bending the thin glass to a minimum bending radius R, wherein the minimum bending radius R is related to the tensile stress σ app as follows:
σ
app
=
E
1
-
v
2
t
2
R
,
wherein E is Young's modulus of the thin glass, t is the thickness of the thin glass, and ν is Poisson's ratio of the thin glass.
5. The method as claimed in claim 4 , further comprising winding the thin glass into a roll, the thin glass comprising a glass ribbon.
6. The method as claimed in claim 5 , wherein the minimum bending radius R is on an inner surface of the roll.
7. The method as claimed in claim 6 , wherein the step of winding comprises winding a length of at least 100 meters into the roll.
8. The method as claimed in claim 1 , wherein the thin glass has a thickness of less than 500 μm.
9. The method as claimed in claim 1 , wherein the thin glass has a thickness of not more than 350 μm.
10. The method as claimed in claim 1 , wherein the tensile stress is at least 21 MPa.
11. The method as claimed in claim 1 , further comprising determining a maximum tensile stress of the thin glass from the mean values σ a , σ e and standard deviations Δ e and Δ a , and wherein the step of subjecting the thin glass to the tensile stress σ app does not exceed the maximum tensile stress.
12. The method as claimed in claim 1 , further comprising determining the mean value σ a of the tensile stress at break for fractures and the mean value σ e of the tensile stress at break for fractures emanating from the edge by subjecting at least twenty samples of the thin glass to a tensile stress until break.
13. The method as claimed in claim 12 , wherein the mean value σ a is determined by a breaking test in which a thin glass sample is fixed annularly and is loaded until break using a stamp that has a curved surface.
14. The method as claimed in claim 12 , wherein the mean value σ e is determined by a bending test in which a thin glass sample is bent uniaxially until break.
15. The method as claimed in claim 1 , further comprising storing the thin glass while subjected to the tensile stress σ app for a period of at least half a year.
16. A thin glass article comprising:
thin glass subjected to a tensile stress σ app smaller than
1.15
·
Min
(
σ
_
a
-
Δ
a
0.4
·
(
1
-
ln
(
A
ref
A
App
Φ
)
)
,
σ
_
e
-
Δ
e
0.4
·
(
1
-
ln
(
L
ref
L
App
Φ
)
)
)
,
wherein σ a is a mean value of a tensile stress at break for fractures in a surface of samples of the thin glass under bending stress,
wherein σ e is a mean value of a tensile stress at break for fractures emanating from an edge of the samples,
wherein L ref is an edge length of the samples and A ref is a surface area of the samples,
wherein Δ e and Δ a denote standard deviations of the mean values σ e and σ a , respectively, and
wherein A app is a surface area of the thin glass, L app is a summated edge length of opposite edges of the thin glass, and Φ is a maximum fracture rate of not more than 0.1 within a period of time of at least half a year.
17. The thin glass article as claimed in claim 16 , wherein the thin glass is wound into a roll having a radius R on an inner surface of the roll that is related to the tensile stress σ app as follows:
σ
app
=
E
1
-
v
2
t
2
R
,
wherein E is Young's modulus, t is a thickness of the thin glass, and ν is Poisson's ratio of the thin glass.
18. The thin glass article as claimed in claim 16 , wherein the tensile stress σ app smaller than
0.93
·
Min
(
σ
_
a
-
Δ
a
0.4
·
(
1
-
ln
(
A
ref
A
app
Φ
)
)
,
σ
_
e
-
Δ
e
0.4
·
(
1
-
ln
(
L
ref
L
app
Φ
)
)
)
.
19. The thin glass article as claimed in claim 16 , wherein the thin glass is subject to a maximum tensile stress of 21 MPa.Cited by (0)
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References (0)
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